Commercial cultivation of plants is a major part of the economy, encompassing not only crops grown for human food and animal feed, but also crops such as cotton grown for fiber, trees grown for lumber, and others, such as flowers grown for beauty. The importance of plants to people and to the economy can hardly be overstated. Plants are subject to constant attack by insects and other animals, fungi, bacteria, viruses, nematodes, and other pathogens. When pathogens find susceptible plants, these attacks can result in the loss of yield and quality, and may result in the loss of entire crops. These losses result in substantial economic harm to the growers and, in some areas of the world, contribute to famine.
There is an on-going need for a means of protecting a variety of trees, crops, flowers, decorative and other plants in the field from pests and pathogens more effectively, at lower cost, and with less effort than by the use of pesticides and other traditional chemical agents. Moreover, what is needed is a means of providing this protection with lower and less lasting damage to the environment than caused by such conventional agents.
Various devices and systems for the application of systemics to plants, seeds, and soil, have been developed in the art. U.S. Pat. No. 5,527,366 discloses a method of applying an herbicide to plants that includes delivering a liquid herbicide solution to the plant foliage in a pressurized jet stream to physically disrupt the surface of the foliage. U.S. Pat. No. 4,291,497 describes a method of introducing a chemical agent into plants by spraying or dipping the plant organs into the agent and allowing the agent to penetrate the plant system. U.S. Pat. Nos. 4,994,487 and 5,575,224 disclose a device for injecting a liquid pesticide (fungicide and herbicide, respectively) into the soil adjacent to the root system of plants. U.S. Pat. No. 4,356,934 discloses a seed treatment method that includes spraying of an emulsion containing an insecticide, fungicide or bactericide, onto the seed prior to planting. U.S. Pat. No. 4,596,206 discloses an apparatus for treatment of seeds with a liquid insecticide-fungicide, prior to planting.